The specific objective of this study is to demonstrate that the endogenous catecholamine epinephrine can destroy nerve terminals in much the same way as does 6-hydroxydopamine. The overall objective of providing this observation is to offer new insight in epinephrine's mechanism of action in the treatment of glaucoma (open angle) and suggest explanations for some of epinephrine's toxic side effects. Electron microscopic analysis is used to provide ultrastructural evidence of the chemical sympathectomy following epinephrine administration.